But one statement stopped me cold: “I truly believe that the single most important career decision that a woman makes is whether she will have a life partner and who that partner is.”

When I became accidentally (albeit, at 39, happily) pregnant, I left my dream portfolio management job as a concession to my child’s father, who took a dim view of babysitting while I jetted off to meet (male) chief executives and drink with (male) colleagues.

My personal circumstances are unusual: most women with graduate degrees don’t have “oops babies”. But leaving a job for a man is not. My departure coincided with a wave of female attrition in my division. When I started there were lots of women, but in the space of a few short years most of us left.

Many of us did not leave because of our kids — we left because of their fathers.

I take issue with a system that expects solutions to the dual-income household to come largely from within that household

The “assortative maters” — similar people who marry each other — left because their husbands did well. One, because her husband was appointed to a high-level position in the Obama administration; another, because she had two young children and a senior executive husband with an insane travel schedule.

Others of us left because it was the husband’s “turn” to develop his career. One married into a family that owned a small business, and they relocated back to his roots on becoming parents. They divorced within a couple of years, leaving her a single parent stranded in a town with reduced career prospects. Similarly, after quitting my job and moving to a small town to accommodate my baby-daddy’s desire to flip fixer-upper houses, I ultimately quit him too.

To sum up: we left because none of us had ended up with the “unicorn” husbands Ms Sandberg lauded in her book — saintly men enough like us to appreciate our ambition, but not threatened by our success. If these mythical creatures have careers, they are not “trump” careers. In some sense they would be a version of 1960s-era housewives, whose misery was grimly detailed in Betty Friedan’s The Feminine Mystique.

I do not take issue with Lean In’s point about the blessing of a supportive spouse — by all means, sign me up for one. But I do take issue with a system that expects solutions to the dual-income household to come largely from within that household.

Our bosses were not there for the tense negotiations over travel calendars we had with our kids’ fathers

Our bosses were not present for the tense negotiations over scheduling and travel calendars with the fathers of our children, or for the anxious moments staring at airport displays, or for arriving home to news that the nanny is quitting — and the subsequent fight with our life partner about who doesn’t travel until we find a replacement.

Women may have made tremendous progress in the workforce since The Feminine Mystique, but corporate support for their widely varying families has not kept pace. Ms Sandberg herself acknowledged this in an essay after her husband’s death: “Some people felt that I did not spend enough time writing about the difficulties women face when they have an unsupportive partner or no partner at all. They were right.”

Even my son recognises the zero-sum game too often played by working parents. He claims he is not planning to have kids, with reasoning wise beyond his seven years: “Because I’ll be too busy working in my bakery.” (He has decided on a career as a baker, perhaps as a defence mechanism against a mother who eschews cooking.)

Joint custody: criterion for success?

Thanks to 50-50 custody, which blurs lines between “mothers” and “fathers” and renders traditionally gendered behaviours androgynous, my son is no stranger to the career sacrifices parents — mothers and fathers — make. And his parents are arguably among the luckier ones, professionally; the silver lining of living without one’s child half the time is greater flexibility to work long hours and travel. But joint custody should surely not be a criterion for career success.

Only when companies start to think about how to address the structural impediments to career and family harmony will we be able to lay Lean In’s partner directive to rest. For the sake of our grandchildren, corporate America should address these twin challenges: two-income households with kids where one income had to shrink, and single-parent homes that cannot accommodate its demands.

The writer is a bond portfolio manager at Weaver Barksdale, an adjunct professor at Columbia Business School — and a veteran manager of conflicting travel and custody schedules